High octane gasoline is needed for modern gasoline engines. Previously, octane numbers were often improved by incorporating various lead-containing additives into the gasoline. As lead-containing additives have been phased out of gasoline for environmental reasons, it has become increasingly necessary to rearrange the structure of the hydrocarbons used in gasoline blending to achieve higher octane ratings. Catalytic reforming of hydrocarbons is a process widely used by refiners for upgrading the octane ratings of gasoline.
In catalytic reforming, a hydrocarbon feedstock of, for example, C5 hydrocarbons to about C11 hydrocarbons, is contacted with a reforming catalyst to convert at least a portion of the heavier hydrocarbons to aromatic hydrocarbons to increase the octane content of gasoline. The catalytic reforming of the heavier hydrocarbons is endothermic and typically requires interstage heating to effectively drive the catalytic reforming reactions to produce a reformate that includes aromatic hydrocarbons. Currently, fuel gas burning radiant heaters that produce heat and hot flue gas are used to provide interstage heating. Refiners are looking for ways to recover waste heat from the hot flue gas to improve processing and production of the reforming products.
Accordingly, it is desirable to provide apparatuses and methods for reforming of hydrocarbons with improved process heat recovery and production of reforming products. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and this background.